JP4178603B2 - Thermal head and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thermal head suitably used for a recording unit such as a printer or a facsimile, and a manufacturing method thereof.
[0002]
[Prior art]
FIG. 8 is a perspective view showing an example of a thermal head.
In FIG. 8, reference numeral 1 denotes a substrate made of a metal such as stainless steel or an alloy containing chromium and aluminum. On the surface of the substrate 1, a linear common electrode portion M is formed so as to protrude.
[0003]
Reference numeral 2 denotes an insulating grace glass layer made of glass or the like formed on the surface of the substrate 1. A portion in the vicinity of the common electrode portion M of the grace glass layer 2 is a raised portion 2a formed so as to rise in a circular arc shape in cross section. In the central portion of the raised portion 2a, the common electrode portion M is exposed from the upper surface.
[0004]
On the surface of the raised portion 2a of the grace glass layer 2, a resistance pattern of a large number of resistors is formed in parallel with each other corresponding to each line of the printer, and the common electrode portion M is sandwiched between these resistance patterns. Both sides are a first heating element 4 and a second heating element 5.
[0005]
One end of the first heating element 4 is connected to the common electrode portion M, and the other end is connected to an individual electrode 6 formed on the surface of the grace glass layer 2.
Meanwhile, one end of the second heating element 5 is connected to the common electrode portion M, and the other end is connected to the collective electrode 7.
[0006]
Such a thermal head can give the minimum energy necessary for color development to the printing paper by the second heating element 5 and can give the energy for coloring at a predetermined gradation by the first heating element 4. Therefore, it is an excellent thermal head that can shorten the time required for printing and improve the printing ability.
[0007]
However, in such a thermal head, since the width of the common electrode portion M of the substrate 1 is narrow, the method of using the photolithography generally used as a method for forming the resistor pattern is used to form the common electrode portion M. When forming the resistor pattern of the resistor, there is a disadvantage that alignment by the photolithography is difficult. For this reason, the position of the resistor is displaced, an abnormality occurs in the resistance value of the resistor, and there is a high possibility that the resistor cannot be used as a thermal head.
Further, in such a thermal head, since the width of the common electrode portion M is very narrow as 50 to 70 μm, it is very difficult to form the common electrode portion M. For example, when the common electrode portion M of 50 μm is formed, an error of about 10 μm is often generated. For this reason, the alignment by the photolithography in forming the resistor pattern is even more difficult.
[0008]
In such a thermal head, since the mechanical characteristics of the substrate 1 made of metal and the grace glass layer 2 made of ceramic are greatly different, the interface 3 between the common electrode portion M of the substrate 1 and the grace glass layer 2 is different. However, there is a disadvantage that structural defects are likely to occur during lapping.
For example, when a thermal head is manufactured by a method using the photolithography, a very thin resistor having a thickness of about 100 nm is formed on the common electrode portion M of the substrate 1 and patterned into a predetermined shape. If minute structural defects due to lapping are present in the common electrode portion M, the resistor R easily breaks at the interface 3 between the common electrode portion M and the grace glass layer 2 as shown in FIG. It was a problem that it was easy to become.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, solves such a problem, and facilitates alignment by photolithography in pattern formation of the resistor R. The common electrode portion M and the grace glass layer 2 It is an object of the present invention to provide a thermal head that can prevent generation of defective products due to disconnection of the resistor R at the interface 3.
Another object is to provide a method for manufacturing the thermal head.
[0010]
[Means for Solving the Problems]
This object is achieved, and the common electrode portion of the shaped line formed on the substrate, on the substrate, a common an insulating Grace glass layer formed on both sides of the electrode portion, the common electrode portion on the front Stories common electrode A resistor composed of a base line resistor formed in the longitudinal direction of the portion and a heating resistor formed so as to intersect with the base line resistor, and one end of the heating resistor formed on the grace glass layer. and bulk electrodes, wherein formed on Grace glass layer, wherein a heating resistor individual electrodes whose other end is connected to, possess a common electrode formed on the resistor, the width of the base line resistor This can be solved by a thermal head that is equal to or smaller than the width of the common electrode portion, and the width of the common electrode portion is less than the width of the common electrode.
The front Symbol challenge, a common electrode portion of the linear is formed on a substrate and on said substrate, said common on both sides of the electrode portion to form an insulating Grace glass layer, the width on the common electrode portion After forming a base line resistor extending in the longitudinal direction of the common electrode portion that is equal to or less than the width of the common electrode portion , and a heat resistor that intersects the base line resistor, the heat generating resistor is formed on the grace glass layer. A thermal head in which a collective electrode is formed so as to be connected to one end and an individual electrode is formed so as to be connected to the other end, and a common electrode having a width exceeding the width of the common electrode portion is formed on the resistor. This can be solved by the manufacturing method.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below.
FIG. 1 is a view showing an example of the thermal head of the present invention.
The thermal head, the width W _R of the resistor Ra formed in the longitudinal direction of the common electrode portion M is, the common electrode portion M or less the width W _M of the width W _M of the common electrode portion M is, common The thermal head is less than the width W _{C of the} electrode C.
[0012]
FIG. 2 is a perspective view showing a substrate used in the thermal head shown in FIG.
The substrate 1 is made of a metal such as stainless steel or an alloy containing chromium and aluminum. Wherein the surface of the substrate 1, a line-shaped common electrode portion M having a constant width W _M are protruded.
[0013]
As shown in FIGS. 3 and 4, a glass grace layer 2 is formed on the substrate 1 so that the upper end of the common electrode portion M is exposed and the vicinity thereof is raised. .
A resistor R is formed on the substrate 1 and the glass grace layer 2 as shown in FIG. The resistor R is abbreviated as a resistor Ra (hereinafter abbreviated as “baseline resistor”) formed in the longitudinal direction of the common electrode portion M and an Rb (hereinafter abbreviated as “heating resistor”) intersecting with the resistor Ra. ), And the width W _R of the base line resistor Ra formed in the longitudinal direction is equal to or less than the width W _M of the common electrode portion M. In other words, the relationship between the width W _R of the base line resistor Ra and the width W _M of the common electrode portion M is expressed by the following equation (1).
W _R ≦ W _M (1)
[0014]
Further, a common electrode C is formed on the resistor R as shown in FIG.
The width W _C of the common electrode film C is set to be larger than the width W _M of the common electrode portion M.
In other words, the relationship between the width W _C of the common electrode film C and the width W _M of the common electrode portion M is expressed by the following equation (2).
W _M ≦ W _c (2)
[0015]
Further, the width W _C of the common electrode film C is desirably 2000 μm or less.
The width W _C of the common electrode C, if set to less than the width W _M of the common electrode portion M, for example, as shown in FIG. 9, the resistor R at the interface between the common electrode portion M Grace glass layer 2 When disconnection occurs, it is not preferable because electricity cannot be passed and generation of defective products cannot be prevented. On the other hand, if the width W _C exceeds 2000 μm, heat loss at the common electrode C increases, which is not preferable.
[0016]
Since the thermal head, the width W _R of the base line resistor Ra which longitudinally formed in the common electrode portion M is not more than the width W _M of the common electrode portion M, the photo in the pattern formation of the resistor R At the time of alignment by lithography, the area hidden by the base line resistor Ra is small, and the positions of the base line resistor Ra and the common electrode portion M can be easily confirmed. Therefore, the alignment can be performed easily.
Therefore, the position of the resistor R is not easily displaced, and defective products are hardly generated.
[0017]
Further, the width W _M of the common electrode portion M is, since it is less than the width W _C of the common electrode C, as shown in FIG. 9, the resistor R is broken at the interface between the common electrode portion M Grace glass layer 2 In this case, since the electricity in the disconnected portion can be passed through the common electrode C, the occurrence of defective products can be prevented.
[0018]
Furthermore, the width W _C of the common electrode C is, by setting not more than 2000 .mu.m, it is possible to minimize heat loss at the common electrode C, a more preferred thermal head.
[0019]
In order to manufacture the thermal head of the present invention, first, as shown in FIG. 2, for example, after cleaning and polishing the substrate 1, patterning is performed by photolithography and etching, as shown in FIG. The linear common electrode portion M is formed in a protruding manner by a processing method such as polishing, cutting, roll processing, pressing, or drawing. The formation of the common electrode portion M can also be performed by a method combining the methods described above.
[0020]
Subsequently, as shown in FIGS. 3 and 4, the glass 1 is formed on the substrate 1 on which the common electrode portion M is formed so that the upper end of the common electrode portion M is exposed and the vicinity thereof is raised. Layer 2 is formed.
The formation of the grace glass layer 2 is preferably performed by a method in which a glass paste or the like is printed by screen printing using a mesh plate and baked, and then lapped and polished.
[0021]
Next, as shown in FIG. 5, a TaSiO ₂ film is formed on the common electrode portion M and the grace glass layer 2 by, for example, a sputtering method, and the width W _R is set to the common electrode by a method such as photolithography. A resistor R having a baseline resistor Ra and a heating resistor Rb that is equal to or smaller than the width W _{M of the} portion M is formed.
Photolithography at this time has a predetermined shape so that the width W _R of the base line resistor Ra formed in the longitudinal direction of the common electrode portion M is equal to or smaller than the width W _M of the common electrode portion M on the photomask. Next, the position of the prescribed resistor Ra on the photomask and the position of the common electrode portion M are aligned using a mask eyeliner.
[0022]
Further, as shown in FIG. 6, the common electrode C is formed on the resistor R by a method of forming the common electrode C so that the width exceeds the width W _M of the common electrode portion M and is 2000 μm or less. Is called.
[0023]
Baseline this manufacturing method for a thermal head, forms a common electrode portion M of the linear on the substrate 1, the common electrode portion on M, is the width W _R is less than the width W _M of the common electrode portion M Since the resistor Ra and the heating resistor Rb are formed, a method of manufacturing a thermal head in which the common electrode C having a width W _C exceeding the width W _M of the common electrode portion M is formed on the resistor R is provided. , the width W _R of the base line resistor Ra is comprised and the common electrode portion M width W _M following, upon alignment by photolithography in the pattern formation of the resistor R, the production method can be carried out easily aligned . For example, the width W _R of the base line resistor Ra, compared with the case of exceeding the width W _M of the common electrode portion M, since less area Hidden baseline resistor Ra, the baseline resistor Ra and the common electrode The position of the portion M is easy to confirm, and the manufacturing method can be easily aligned.
Therefore, the position of the resistor R is not easily displaced, and the manufacturing method is less likely to cause defective products.
[0024]
【Example】
EXAMPLES Hereinafter, although an Example is shown and this invention is demonstrated in detail, this invention is not limited only to this Example.
As shown in FIG. 2, a common electrode portion M having a width W _{M of} 70 μm is formed on the surface of the stainless steel substrate 1 and then the upper end of the common electrode portion M is formed as shown in FIGS. The grace glass layer 2 is formed so as to be in an exposed state and the vicinity thereof is raised, and subsequently, the photolithography is used on the common electrode portion M and the grace glass layer 2 as shown in FIG. Thus, a resistor _{R having} a width W _{R of} 30 μm of the baseline resistor Ra, a width of 75 μm of the heating resistor Rb, a pitch of 10 μm between the heating resistors Rb, and a thickness of 100 nm is formed to form a resistor pattern, Further, a common electrode C having a width WM of 80 μm as shown in FIG. 6 was formed on the resistor R to obtain a thermal head.
[0025]
As a result, it was confirmed that alignment by photolithography in pattern formation of the resistor R was easy, and a thermal head could be easily obtained.
[0026]
【The invention's effect】
As described above, the thermal head of the present invention includes a linear common electrode portion formed on a substrate, an insulating grace glass layer formed on both sides of the common electrode portion on the substrate, common baseline resistor longitudinally formed before Symbol common electrode portion electrode on part, and a resistor body consisting of the formed heating resistor so as to intersect this, formed on the Grace glass layer, wherein A collective electrode to which one end of the heating resistor is connected, an individual electrode formed on the grace glass layer and connected to the other end of the heating resistor, and a common electrode formed on the resistor. In addition, since the width of the baseline resistor is equal to or less than the width of the common electrode portion, and the width of the common electrode portion is less than the width of the common electrode, alignment by photolithography is easy. thing In addition, when the resistor is disconnected at the interface between the common electrode portion and the grace glass layer, electricity can be passed through the common electrode, so that a thermal head that can prevent the occurrence of defective products can be obtained. be able to.
[0028]
The method for manufacturing a thermal head according to the present invention includes forming a linear common electrode portion on a substrate , forming an insulating grace glass layer on both sides of the common electrode portion on the substrate, and And forming a resistor composed of a base line resistor extending in the longitudinal direction of the common electrode portion having a width equal to or less than the width of the common electrode portion , and a heating resistor intersecting with the base line resistor, on the grace glass layer, A batch electrode is formed so as to be connected to one end of the heating resistor and an individual electrode is formed so as to be connected to the other end, and a common electrode having a width exceeding the width of the common electrode portion is formed on the resistor. Since the width of the resistor formed in the length direction of the common electrode portion is narrower than the width of the common electrode portion, the photolithography in the resistor pattern formation is performed. Since the alignment with it becomes easy, hardly causes misalignment of the position of the resistor, defective products can be manufactured method hardly occurs.
[Brief description of the drawings]
FIG. 1 is a diagram showing an example of a thermal head of the present invention.
2 is a perspective view showing a substrate used in the thermal head shown in FIG. 1. FIG.
FIG. 3 is a view showing a state in which a grace glass layer is formed on the substrate shown in FIG. 2;
4 is a cross-sectional view showing a state in which a grace glass layer is formed on the substrate shown in FIG. 2;
5 is a view showing a state in which a resistor is formed on the common electrode portion and the grace glass layer shown in FIGS. 3 and 4. FIG.
6 is a view showing a state in which a common electrode is formed on the resistor shown in FIG. 5. FIG.
FIG. 7 is a view showing a state of a resistor formed in an example.
FIG. 8 is a perspective view showing an example of a thermal head.
FIG. 9 is a diagram showing an example of a conventional thermal head.
[Explanation of symbols]
1 Substrate M Common Electrode Portion R Resistor Ra Baseline Resistor C Common Electrode

Claims (2)

A linear common electrode portion formed on the substrate;
An insulating grace glass layer formed on both sides of the common electrode portion on the substrate;
A resistor made from the common electrode before on the part's rating baseline resistor longitudinally formed in the common electrode portion, and a heating resistor that is formed so as to intersect therewith,
A collective electrode formed on the grace glass layer and connected to one end of the heating resistor;
An individual electrode formed on the grace glass layer and connected to the other end of the heating resistor;
Possess a common electrode formed on the resistor,
The width of the baseline resistor is equal to or less than the width of the common electrode portion;
The thermal head according to claim 1, wherein a width of the common electrode portion is less than a width of the common electrode. A linear common electrode portion is formed on the substrate,
Forming an insulating grace glass layer on both sides of the common electrode portion on the substrate;
After the width common electrode on portions to form a longitudinally extending base line resistor, and the resistor formed of the heating resistor which intersects with this of the common electrode portion is a width less of the common electrode portion,
On the grace glass layer, a batch electrode is formed so as to be connected to one end of the heating resistor and an individual electrode is formed so as to be connected to the other end.
A method of manufacturing a thermal head, comprising: forming a common electrode having a width exceeding the width of the common electrode portion on the resistor.

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